2 * drivers/base/core.c - core driver model code (device registration, etc)
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
6 * Copyright (c) 2006 Greg Kroah-Hartman <gregkh@suse.de>
7 * Copyright (c) 2006 Novell, Inc.
9 * This file is released under the GPLv2
13 #include <linux/device.h>
14 #include <linux/err.h>
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/string.h>
19 #include <linux/kdev_t.h>
20 #include <linux/notifier.h>
22 #include <linux/of_device.h>
23 #include <linux/genhd.h>
24 #include <linux/kallsyms.h>
25 #include <linux/mutex.h>
26 #include <linux/pm_runtime.h>
27 #include <linux/netdevice.h>
28 #include <linux/sysfs.h>
31 #include "power/power.h"
33 #ifdef CONFIG_SYSFS_DEPRECATED
34 #ifdef CONFIG_SYSFS_DEPRECATED_V2
35 long sysfs_deprecated
= 1;
37 long sysfs_deprecated
= 0;
39 static int __init
sysfs_deprecated_setup(char *arg
)
41 return kstrtol(arg
, 10, &sysfs_deprecated
);
43 early_param("sysfs.deprecated", sysfs_deprecated_setup
);
46 int (*platform_notify
)(struct device
*dev
) = NULL
;
47 int (*platform_notify_remove
)(struct device
*dev
) = NULL
;
48 static struct kobject
*dev_kobj
;
49 struct kobject
*sysfs_dev_char_kobj
;
50 struct kobject
*sysfs_dev_block_kobj
;
52 static DEFINE_MUTEX(device_hotplug_lock
);
54 void lock_device_hotplug(void)
56 mutex_lock(&device_hotplug_lock
);
59 void unlock_device_hotplug(void)
61 mutex_unlock(&device_hotplug_lock
);
64 int lock_device_hotplug_sysfs(void)
66 if (mutex_trylock(&device_hotplug_lock
))
69 /* Avoid busy looping (5 ms of sleep should do). */
71 return restart_syscall();
75 static inline int device_is_not_partition(struct device
*dev
)
77 return !(dev
->type
== &part_type
);
80 static inline int device_is_not_partition(struct device
*dev
)
87 * dev_driver_string - Return a device's driver name, if at all possible
88 * @dev: struct device to get the name of
90 * Will return the device's driver's name if it is bound to a device. If
91 * the device is not bound to a driver, it will return the name of the bus
92 * it is attached to. If it is not attached to a bus either, an empty
93 * string will be returned.
95 const char *dev_driver_string(const struct device
*dev
)
97 struct device_driver
*drv
;
99 /* dev->driver can change to NULL underneath us because of unbinding,
100 * so be careful about accessing it. dev->bus and dev->class should
101 * never change once they are set, so they don't need special care.
103 drv
= ACCESS_ONCE(dev
->driver
);
104 return drv
? drv
->name
:
105 (dev
->bus
? dev
->bus
->name
:
106 (dev
->class ? dev
->class->name
: ""));
108 EXPORT_SYMBOL(dev_driver_string
);
110 #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
112 static ssize_t
dev_attr_show(struct kobject
*kobj
, struct attribute
*attr
,
115 struct device_attribute
*dev_attr
= to_dev_attr(attr
);
116 struct device
*dev
= kobj_to_dev(kobj
);
120 ret
= dev_attr
->show(dev
, dev_attr
, buf
);
121 if (ret
>= (ssize_t
)PAGE_SIZE
) {
122 print_symbol("dev_attr_show: %s returned bad count\n",
123 (unsigned long)dev_attr
->show
);
128 static ssize_t
dev_attr_store(struct kobject
*kobj
, struct attribute
*attr
,
129 const char *buf
, size_t count
)
131 struct device_attribute
*dev_attr
= to_dev_attr(attr
);
132 struct device
*dev
= kobj_to_dev(kobj
);
136 ret
= dev_attr
->store(dev
, dev_attr
, buf
, count
);
140 static const struct sysfs_ops dev_sysfs_ops
= {
141 .show
= dev_attr_show
,
142 .store
= dev_attr_store
,
145 #define to_ext_attr(x) container_of(x, struct dev_ext_attribute, attr)
147 ssize_t
device_store_ulong(struct device
*dev
,
148 struct device_attribute
*attr
,
149 const char *buf
, size_t size
)
151 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
153 unsigned long new = simple_strtoul(buf
, &end
, 0);
156 *(unsigned long *)(ea
->var
) = new;
157 /* Always return full write size even if we didn't consume all */
160 EXPORT_SYMBOL_GPL(device_store_ulong
);
162 ssize_t
device_show_ulong(struct device
*dev
,
163 struct device_attribute
*attr
,
166 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
167 return snprintf(buf
, PAGE_SIZE
, "%lx\n", *(unsigned long *)(ea
->var
));
169 EXPORT_SYMBOL_GPL(device_show_ulong
);
171 ssize_t
device_store_int(struct device
*dev
,
172 struct device_attribute
*attr
,
173 const char *buf
, size_t size
)
175 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
177 long new = simple_strtol(buf
, &end
, 0);
178 if (end
== buf
|| new > INT_MAX
|| new < INT_MIN
)
180 *(int *)(ea
->var
) = new;
181 /* Always return full write size even if we didn't consume all */
184 EXPORT_SYMBOL_GPL(device_store_int
);
186 ssize_t
device_show_int(struct device
*dev
,
187 struct device_attribute
*attr
,
190 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
192 return snprintf(buf
, PAGE_SIZE
, "%d\n", *(int *)(ea
->var
));
194 EXPORT_SYMBOL_GPL(device_show_int
);
196 ssize_t
device_store_bool(struct device
*dev
, struct device_attribute
*attr
,
197 const char *buf
, size_t size
)
199 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
201 if (strtobool(buf
, ea
->var
) < 0)
206 EXPORT_SYMBOL_GPL(device_store_bool
);
208 ssize_t
device_show_bool(struct device
*dev
, struct device_attribute
*attr
,
211 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
213 return snprintf(buf
, PAGE_SIZE
, "%d\n", *(bool *)(ea
->var
));
215 EXPORT_SYMBOL_GPL(device_show_bool
);
218 * device_release - free device structure.
219 * @kobj: device's kobject.
221 * This is called once the reference count for the object
222 * reaches 0. We forward the call to the device's release
223 * method, which should handle actually freeing the structure.
225 static void device_release(struct kobject
*kobj
)
227 struct device
*dev
= kobj_to_dev(kobj
);
228 struct device_private
*p
= dev
->p
;
231 * Some platform devices are driven without driver attached
232 * and managed resources may have been acquired. Make sure
233 * all resources are released.
235 * Drivers still can add resources into device after device
236 * is deleted but alive, so release devres here to avoid
237 * possible memory leak.
239 devres_release_all(dev
);
243 else if (dev
->type
&& dev
->type
->release
)
244 dev
->type
->release(dev
);
245 else if (dev
->class && dev
->class->dev_release
)
246 dev
->class->dev_release(dev
);
248 WARN(1, KERN_ERR
"Device '%s' does not have a release() "
249 "function, it is broken and must be fixed.\n",
254 static const void *device_namespace(struct kobject
*kobj
)
256 struct device
*dev
= kobj_to_dev(kobj
);
257 const void *ns
= NULL
;
259 if (dev
->class && dev
->class->ns_type
)
260 ns
= dev
->class->namespace(dev
);
265 static struct kobj_type device_ktype
= {
266 .release
= device_release
,
267 .sysfs_ops
= &dev_sysfs_ops
,
268 .namespace = device_namespace
,
272 static int dev_uevent_filter(struct kset
*kset
, struct kobject
*kobj
)
274 struct kobj_type
*ktype
= get_ktype(kobj
);
276 if (ktype
== &device_ktype
) {
277 struct device
*dev
= kobj_to_dev(kobj
);
286 static const char *dev_uevent_name(struct kset
*kset
, struct kobject
*kobj
)
288 struct device
*dev
= kobj_to_dev(kobj
);
291 return dev
->bus
->name
;
293 return dev
->class->name
;
297 static int dev_uevent(struct kset
*kset
, struct kobject
*kobj
,
298 struct kobj_uevent_env
*env
)
300 struct device
*dev
= kobj_to_dev(kobj
);
303 /* add device node properties if present */
304 if (MAJOR(dev
->devt
)) {
308 kuid_t uid
= GLOBAL_ROOT_UID
;
309 kgid_t gid
= GLOBAL_ROOT_GID
;
311 add_uevent_var(env
, "MAJOR=%u", MAJOR(dev
->devt
));
312 add_uevent_var(env
, "MINOR=%u", MINOR(dev
->devt
));
313 name
= device_get_devnode(dev
, &mode
, &uid
, &gid
, &tmp
);
315 add_uevent_var(env
, "DEVNAME=%s", name
);
317 add_uevent_var(env
, "DEVMODE=%#o", mode
& 0777);
318 if (!uid_eq(uid
, GLOBAL_ROOT_UID
))
319 add_uevent_var(env
, "DEVUID=%u", from_kuid(&init_user_ns
, uid
));
320 if (!gid_eq(gid
, GLOBAL_ROOT_GID
))
321 add_uevent_var(env
, "DEVGID=%u", from_kgid(&init_user_ns
, gid
));
326 if (dev
->type
&& dev
->type
->name
)
327 add_uevent_var(env
, "DEVTYPE=%s", dev
->type
->name
);
330 add_uevent_var(env
, "DRIVER=%s", dev
->driver
->name
);
332 /* Add common DT information about the device */
333 of_device_uevent(dev
, env
);
335 /* have the bus specific function add its stuff */
336 if (dev
->bus
&& dev
->bus
->uevent
) {
337 retval
= dev
->bus
->uevent(dev
, env
);
339 pr_debug("device: '%s': %s: bus uevent() returned %d\n",
340 dev_name(dev
), __func__
, retval
);
343 /* have the class specific function add its stuff */
344 if (dev
->class && dev
->class->dev_uevent
) {
345 retval
= dev
->class->dev_uevent(dev
, env
);
347 pr_debug("device: '%s': %s: class uevent() "
348 "returned %d\n", dev_name(dev
),
352 /* have the device type specific function add its stuff */
353 if (dev
->type
&& dev
->type
->uevent
) {
354 retval
= dev
->type
->uevent(dev
, env
);
356 pr_debug("device: '%s': %s: dev_type uevent() "
357 "returned %d\n", dev_name(dev
),
364 static const struct kset_uevent_ops device_uevent_ops
= {
365 .filter
= dev_uevent_filter
,
366 .name
= dev_uevent_name
,
367 .uevent
= dev_uevent
,
370 static ssize_t
uevent_show(struct device
*dev
, struct device_attribute
*attr
,
373 struct kobject
*top_kobj
;
375 struct kobj_uevent_env
*env
= NULL
;
380 /* search the kset, the device belongs to */
381 top_kobj
= &dev
->kobj
;
382 while (!top_kobj
->kset
&& top_kobj
->parent
)
383 top_kobj
= top_kobj
->parent
;
387 kset
= top_kobj
->kset
;
388 if (!kset
->uevent_ops
|| !kset
->uevent_ops
->uevent
)
392 if (kset
->uevent_ops
&& kset
->uevent_ops
->filter
)
393 if (!kset
->uevent_ops
->filter(kset
, &dev
->kobj
))
396 env
= kzalloc(sizeof(struct kobj_uevent_env
), GFP_KERNEL
);
400 /* let the kset specific function add its keys */
401 retval
= kset
->uevent_ops
->uevent(kset
, &dev
->kobj
, env
);
405 /* copy keys to file */
406 for (i
= 0; i
< env
->envp_idx
; i
++)
407 count
+= sprintf(&buf
[count
], "%s\n", env
->envp
[i
]);
413 static ssize_t
uevent_store(struct device
*dev
, struct device_attribute
*attr
,
414 const char *buf
, size_t count
)
416 enum kobject_action action
;
418 if (kobject_action_type(buf
, count
, &action
) == 0)
419 kobject_uevent(&dev
->kobj
, action
);
421 dev_err(dev
, "uevent: unknown action-string\n");
424 static DEVICE_ATTR_RW(uevent
);
426 static ssize_t
online_show(struct device
*dev
, struct device_attribute
*attr
,
434 return sprintf(buf
, "%u\n", val
);
437 static ssize_t
online_store(struct device
*dev
, struct device_attribute
*attr
,
438 const char *buf
, size_t count
)
443 ret
= strtobool(buf
, &val
);
447 ret
= lock_device_hotplug_sysfs();
451 ret
= val
? device_online(dev
) : device_offline(dev
);
452 unlock_device_hotplug();
453 return ret
< 0 ? ret
: count
;
455 static DEVICE_ATTR_RW(online
);
457 int device_add_groups(struct device
*dev
, const struct attribute_group
**groups
)
459 return sysfs_create_groups(&dev
->kobj
, groups
);
462 void device_remove_groups(struct device
*dev
,
463 const struct attribute_group
**groups
)
465 sysfs_remove_groups(&dev
->kobj
, groups
);
468 static int device_add_attrs(struct device
*dev
)
470 struct class *class = dev
->class;
471 const struct device_type
*type
= dev
->type
;
475 error
= device_add_groups(dev
, class->dev_groups
);
481 error
= device_add_groups(dev
, type
->groups
);
483 goto err_remove_class_groups
;
486 error
= device_add_groups(dev
, dev
->groups
);
488 goto err_remove_type_groups
;
490 if (device_supports_offline(dev
) && !dev
->offline_disabled
) {
491 error
= device_create_file(dev
, &dev_attr_online
);
493 goto err_remove_dev_groups
;
498 err_remove_dev_groups
:
499 device_remove_groups(dev
, dev
->groups
);
500 err_remove_type_groups
:
502 device_remove_groups(dev
, type
->groups
);
503 err_remove_class_groups
:
505 device_remove_groups(dev
, class->dev_groups
);
510 static void device_remove_attrs(struct device
*dev
)
512 struct class *class = dev
->class;
513 const struct device_type
*type
= dev
->type
;
515 device_remove_file(dev
, &dev_attr_online
);
516 device_remove_groups(dev
, dev
->groups
);
519 device_remove_groups(dev
, type
->groups
);
522 device_remove_groups(dev
, class->dev_groups
);
525 static ssize_t
dev_show(struct device
*dev
, struct device_attribute
*attr
,
528 return print_dev_t(buf
, dev
->devt
);
530 static DEVICE_ATTR_RO(dev
);
533 struct kset
*devices_kset
;
536 * device_create_file - create sysfs attribute file for device.
538 * @attr: device attribute descriptor.
540 int device_create_file(struct device
*dev
,
541 const struct device_attribute
*attr
)
546 WARN(((attr
->attr
.mode
& S_IWUGO
) && !attr
->store
),
547 "Attribute %s: write permission without 'store'\n",
549 WARN(((attr
->attr
.mode
& S_IRUGO
) && !attr
->show
),
550 "Attribute %s: read permission without 'show'\n",
552 error
= sysfs_create_file(&dev
->kobj
, &attr
->attr
);
557 EXPORT_SYMBOL_GPL(device_create_file
);
560 * device_remove_file - remove sysfs attribute file.
562 * @attr: device attribute descriptor.
564 void device_remove_file(struct device
*dev
,
565 const struct device_attribute
*attr
)
568 sysfs_remove_file(&dev
->kobj
, &attr
->attr
);
570 EXPORT_SYMBOL_GPL(device_remove_file
);
573 * device_remove_file_self - remove sysfs attribute file from its own method.
575 * @attr: device attribute descriptor.
577 * See kernfs_remove_self() for details.
579 bool device_remove_file_self(struct device
*dev
,
580 const struct device_attribute
*attr
)
583 return sysfs_remove_file_self(&dev
->kobj
, &attr
->attr
);
587 EXPORT_SYMBOL_GPL(device_remove_file_self
);
590 * device_create_bin_file - create sysfs binary attribute file for device.
592 * @attr: device binary attribute descriptor.
594 int device_create_bin_file(struct device
*dev
,
595 const struct bin_attribute
*attr
)
599 error
= sysfs_create_bin_file(&dev
->kobj
, attr
);
602 EXPORT_SYMBOL_GPL(device_create_bin_file
);
605 * device_remove_bin_file - remove sysfs binary attribute file
607 * @attr: device binary attribute descriptor.
609 void device_remove_bin_file(struct device
*dev
,
610 const struct bin_attribute
*attr
)
613 sysfs_remove_bin_file(&dev
->kobj
, attr
);
615 EXPORT_SYMBOL_GPL(device_remove_bin_file
);
617 static void klist_children_get(struct klist_node
*n
)
619 struct device_private
*p
= to_device_private_parent(n
);
620 struct device
*dev
= p
->device
;
625 static void klist_children_put(struct klist_node
*n
)
627 struct device_private
*p
= to_device_private_parent(n
);
628 struct device
*dev
= p
->device
;
634 * device_initialize - init device structure.
637 * This prepares the device for use by other layers by initializing
639 * It is the first half of device_register(), if called by
640 * that function, though it can also be called separately, so one
641 * may use @dev's fields. In particular, get_device()/put_device()
642 * may be used for reference counting of @dev after calling this
645 * All fields in @dev must be initialized by the caller to 0, except
646 * for those explicitly set to some other value. The simplest
647 * approach is to use kzalloc() to allocate the structure containing
650 * NOTE: Use put_device() to give up your reference instead of freeing
651 * @dev directly once you have called this function.
653 void device_initialize(struct device
*dev
)
655 dev
->kobj
.kset
= devices_kset
;
656 kobject_init(&dev
->kobj
, &device_ktype
);
657 INIT_LIST_HEAD(&dev
->dma_pools
);
658 mutex_init(&dev
->mutex
);
659 lockdep_set_novalidate_class(&dev
->mutex
);
660 spin_lock_init(&dev
->devres_lock
);
661 INIT_LIST_HEAD(&dev
->devres_head
);
663 set_dev_node(dev
, -1);
665 EXPORT_SYMBOL_GPL(device_initialize
);
667 struct kobject
*virtual_device_parent(struct device
*dev
)
669 static struct kobject
*virtual_dir
= NULL
;
672 virtual_dir
= kobject_create_and_add("virtual",
673 &devices_kset
->kobj
);
683 #define to_class_dir(obj) container_of(obj, struct class_dir, kobj)
685 static void class_dir_release(struct kobject
*kobj
)
687 struct class_dir
*dir
= to_class_dir(kobj
);
692 struct kobj_ns_type_operations
*class_dir_child_ns_type(struct kobject
*kobj
)
694 struct class_dir
*dir
= to_class_dir(kobj
);
695 return dir
->class->ns_type
;
698 static struct kobj_type class_dir_ktype
= {
699 .release
= class_dir_release
,
700 .sysfs_ops
= &kobj_sysfs_ops
,
701 .child_ns_type
= class_dir_child_ns_type
704 static struct kobject
*
705 class_dir_create_and_add(struct class *class, struct kobject
*parent_kobj
)
707 struct class_dir
*dir
;
710 dir
= kzalloc(sizeof(*dir
), GFP_KERNEL
);
715 kobject_init(&dir
->kobj
, &class_dir_ktype
);
717 dir
->kobj
.kset
= &class->p
->glue_dirs
;
719 retval
= kobject_add(&dir
->kobj
, parent_kobj
, "%s", class->name
);
721 kobject_put(&dir
->kobj
);
727 static DEFINE_MUTEX(gdp_mutex
);
729 static struct kobject
*get_device_parent(struct device
*dev
,
730 struct device
*parent
)
733 struct kobject
*kobj
= NULL
;
734 struct kobject
*parent_kobj
;
738 /* block disks show up in /sys/block */
739 if (sysfs_deprecated
&& dev
->class == &block_class
) {
740 if (parent
&& parent
->class == &block_class
)
741 return &parent
->kobj
;
742 return &block_class
.p
->subsys
.kobj
;
747 * If we have no parent, we live in "virtual".
748 * Class-devices with a non class-device as parent, live
749 * in a "glue" directory to prevent namespace collisions.
752 parent_kobj
= virtual_device_parent(dev
);
753 else if (parent
->class && !dev
->class->ns_type
)
754 return &parent
->kobj
;
756 parent_kobj
= &parent
->kobj
;
758 mutex_lock(&gdp_mutex
);
760 /* find our class-directory at the parent and reference it */
761 spin_lock(&dev
->class->p
->glue_dirs
.list_lock
);
762 list_for_each_entry(k
, &dev
->class->p
->glue_dirs
.list
, entry
)
763 if (k
->parent
== parent_kobj
) {
764 kobj
= kobject_get(k
);
767 spin_unlock(&dev
->class->p
->glue_dirs
.list_lock
);
769 mutex_unlock(&gdp_mutex
);
773 /* or create a new class-directory at the parent device */
774 k
= class_dir_create_and_add(dev
->class, parent_kobj
);
775 /* do not emit an uevent for this simple "glue" directory */
776 mutex_unlock(&gdp_mutex
);
780 /* subsystems can specify a default root directory for their devices */
781 if (!parent
&& dev
->bus
&& dev
->bus
->dev_root
)
782 return &dev
->bus
->dev_root
->kobj
;
785 return &parent
->kobj
;
789 static void cleanup_glue_dir(struct device
*dev
, struct kobject
*glue_dir
)
791 /* see if we live in a "glue" directory */
792 if (!glue_dir
|| !dev
->class ||
793 glue_dir
->kset
!= &dev
->class->p
->glue_dirs
)
796 mutex_lock(&gdp_mutex
);
797 kobject_put(glue_dir
);
798 mutex_unlock(&gdp_mutex
);
801 static void cleanup_device_parent(struct device
*dev
)
803 cleanup_glue_dir(dev
, dev
->kobj
.parent
);
806 static int device_add_class_symlinks(struct device
*dev
)
813 error
= sysfs_create_link(&dev
->kobj
,
814 &dev
->class->p
->subsys
.kobj
,
819 if (dev
->parent
&& device_is_not_partition(dev
)) {
820 error
= sysfs_create_link(&dev
->kobj
, &dev
->parent
->kobj
,
827 /* /sys/block has directories and does not need symlinks */
828 if (sysfs_deprecated
&& dev
->class == &block_class
)
832 /* link in the class directory pointing to the device */
833 error
= sysfs_create_link(&dev
->class->p
->subsys
.kobj
,
834 &dev
->kobj
, dev_name(dev
));
841 sysfs_remove_link(&dev
->kobj
, "device");
844 sysfs_remove_link(&dev
->kobj
, "subsystem");
849 static void device_remove_class_symlinks(struct device
*dev
)
854 if (dev
->parent
&& device_is_not_partition(dev
))
855 sysfs_remove_link(&dev
->kobj
, "device");
856 sysfs_remove_link(&dev
->kobj
, "subsystem");
858 if (sysfs_deprecated
&& dev
->class == &block_class
)
861 sysfs_delete_link(&dev
->class->p
->subsys
.kobj
, &dev
->kobj
, dev_name(dev
));
865 * dev_set_name - set a device name
867 * @fmt: format string for the device's name
869 int dev_set_name(struct device
*dev
, const char *fmt
, ...)
874 va_start(vargs
, fmt
);
875 err
= kobject_set_name_vargs(&dev
->kobj
, fmt
, vargs
);
879 EXPORT_SYMBOL_GPL(dev_set_name
);
882 * device_to_dev_kobj - select a /sys/dev/ directory for the device
885 * By default we select char/ for new entries. Setting class->dev_obj
886 * to NULL prevents an entry from being created. class->dev_kobj must
887 * be set (or cleared) before any devices are registered to the class
888 * otherwise device_create_sys_dev_entry() and
889 * device_remove_sys_dev_entry() will disagree about the presence of
892 static struct kobject
*device_to_dev_kobj(struct device
*dev
)
894 struct kobject
*kobj
;
897 kobj
= dev
->class->dev_kobj
;
899 kobj
= sysfs_dev_char_kobj
;
904 static int device_create_sys_dev_entry(struct device
*dev
)
906 struct kobject
*kobj
= device_to_dev_kobj(dev
);
911 format_dev_t(devt_str
, dev
->devt
);
912 error
= sysfs_create_link(kobj
, &dev
->kobj
, devt_str
);
918 static void device_remove_sys_dev_entry(struct device
*dev
)
920 struct kobject
*kobj
= device_to_dev_kobj(dev
);
924 format_dev_t(devt_str
, dev
->devt
);
925 sysfs_remove_link(kobj
, devt_str
);
929 int device_private_init(struct device
*dev
)
931 dev
->p
= kzalloc(sizeof(*dev
->p
), GFP_KERNEL
);
934 dev
->p
->device
= dev
;
935 klist_init(&dev
->p
->klist_children
, klist_children_get
,
937 INIT_LIST_HEAD(&dev
->p
->deferred_probe
);
942 * device_add - add device to device hierarchy.
945 * This is part 2 of device_register(), though may be called
946 * separately _iff_ device_initialize() has been called separately.
948 * This adds @dev to the kobject hierarchy via kobject_add(), adds it
949 * to the global and sibling lists for the device, then
950 * adds it to the other relevant subsystems of the driver model.
952 * Do not call this routine or device_register() more than once for
953 * any device structure. The driver model core is not designed to work
954 * with devices that get unregistered and then spring back to life.
955 * (Among other things, it's very hard to guarantee that all references
956 * to the previous incarnation of @dev have been dropped.) Allocate
957 * and register a fresh new struct device instead.
959 * NOTE: _Never_ directly free @dev after calling this function, even
960 * if it returned an error! Always use put_device() to give up your
963 int device_add(struct device
*dev
)
965 struct device
*parent
= NULL
;
966 struct kobject
*kobj
;
967 struct class_interface
*class_intf
;
970 dev
= get_device(dev
);
975 error
= device_private_init(dev
);
981 * for statically allocated devices, which should all be converted
982 * some day, we need to initialize the name. We prevent reading back
983 * the name, and force the use of dev_name()
985 if (dev
->init_name
) {
986 dev_set_name(dev
, "%s", dev
->init_name
);
987 dev
->init_name
= NULL
;
990 /* subsystems can specify simple device enumeration */
991 if (!dev_name(dev
) && dev
->bus
&& dev
->bus
->dev_name
)
992 dev_set_name(dev
, "%s%u", dev
->bus
->dev_name
, dev
->id
);
994 if (!dev_name(dev
)) {
999 pr_debug("device: '%s': %s\n", dev_name(dev
), __func__
);
1001 parent
= get_device(dev
->parent
);
1002 kobj
= get_device_parent(dev
, parent
);
1004 dev
->kobj
.parent
= kobj
;
1006 /* use parent numa_node */
1008 set_dev_node(dev
, dev_to_node(parent
));
1010 /* first, register with generic layer. */
1011 /* we require the name to be set before, and pass NULL */
1012 error
= kobject_add(&dev
->kobj
, dev
->kobj
.parent
, NULL
);
1016 /* notify platform of device entry */
1017 if (platform_notify
)
1018 platform_notify(dev
);
1020 error
= device_create_file(dev
, &dev_attr_uevent
);
1024 if (MAJOR(dev
->devt
)) {
1025 error
= device_create_file(dev
, &dev_attr_dev
);
1027 goto ueventattrError
;
1029 error
= device_create_sys_dev_entry(dev
);
1033 devtmpfs_create_node(dev
);
1036 error
= device_add_class_symlinks(dev
);
1039 error
= device_add_attrs(dev
);
1042 error
= bus_add_device(dev
);
1045 error
= dpm_sysfs_add(dev
);
1050 /* Notify clients of device addition. This call must come
1051 * after dpm_sysfs_add() and before kobject_uevent().
1054 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
1055 BUS_NOTIFY_ADD_DEVICE
, dev
);
1057 kobject_uevent(&dev
->kobj
, KOBJ_ADD
);
1058 bus_probe_device(dev
);
1060 klist_add_tail(&dev
->p
->knode_parent
,
1061 &parent
->p
->klist_children
);
1064 mutex_lock(&dev
->class->p
->mutex
);
1065 /* tie the class to the device */
1066 klist_add_tail(&dev
->knode_class
,
1067 &dev
->class->p
->klist_devices
);
1069 /* notify any interfaces that the device is here */
1070 list_for_each_entry(class_intf
,
1071 &dev
->class->p
->interfaces
, node
)
1072 if (class_intf
->add_dev
)
1073 class_intf
->add_dev(dev
, class_intf
);
1074 mutex_unlock(&dev
->class->p
->mutex
);
1080 bus_remove_device(dev
);
1082 device_remove_attrs(dev
);
1084 device_remove_class_symlinks(dev
);
1086 if (MAJOR(dev
->devt
))
1087 devtmpfs_delete_node(dev
);
1088 if (MAJOR(dev
->devt
))
1089 device_remove_sys_dev_entry(dev
);
1091 if (MAJOR(dev
->devt
))
1092 device_remove_file(dev
, &dev_attr_dev
);
1094 device_remove_file(dev
, &dev_attr_uevent
);
1096 kobject_uevent(&dev
->kobj
, KOBJ_REMOVE
);
1097 kobject_del(&dev
->kobj
);
1099 cleanup_device_parent(dev
);
1107 EXPORT_SYMBOL_GPL(device_add
);
1110 * device_register - register a device with the system.
1111 * @dev: pointer to the device structure
1113 * This happens in two clean steps - initialize the device
1114 * and add it to the system. The two steps can be called
1115 * separately, but this is the easiest and most common.
1116 * I.e. you should only call the two helpers separately if
1117 * have a clearly defined need to use and refcount the device
1118 * before it is added to the hierarchy.
1120 * For more information, see the kerneldoc for device_initialize()
1123 * NOTE: _Never_ directly free @dev after calling this function, even
1124 * if it returned an error! Always use put_device() to give up the
1125 * reference initialized in this function instead.
1127 int device_register(struct device
*dev
)
1129 device_initialize(dev
);
1130 return device_add(dev
);
1132 EXPORT_SYMBOL_GPL(device_register
);
1135 * get_device - increment reference count for device.
1138 * This simply forwards the call to kobject_get(), though
1139 * we do take care to provide for the case that we get a NULL
1140 * pointer passed in.
1142 struct device
*get_device(struct device
*dev
)
1144 return dev
? kobj_to_dev(kobject_get(&dev
->kobj
)) : NULL
;
1146 EXPORT_SYMBOL_GPL(get_device
);
1149 * put_device - decrement reference count.
1150 * @dev: device in question.
1152 void put_device(struct device
*dev
)
1154 /* might_sleep(); */
1156 kobject_put(&dev
->kobj
);
1158 EXPORT_SYMBOL_GPL(put_device
);
1161 * device_del - delete device from system.
1164 * This is the first part of the device unregistration
1165 * sequence. This removes the device from the lists we control
1166 * from here, has it removed from the other driver model
1167 * subsystems it was added to in device_add(), and removes it
1168 * from the kobject hierarchy.
1170 * NOTE: this should be called manually _iff_ device_add() was
1171 * also called manually.
1173 void device_del(struct device
*dev
)
1175 struct device
*parent
= dev
->parent
;
1176 struct class_interface
*class_intf
;
1178 /* Notify clients of device removal. This call must come
1179 * before dpm_sysfs_remove().
1182 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
1183 BUS_NOTIFY_DEL_DEVICE
, dev
);
1184 dpm_sysfs_remove(dev
);
1186 klist_del(&dev
->p
->knode_parent
);
1187 if (MAJOR(dev
->devt
)) {
1188 devtmpfs_delete_node(dev
);
1189 device_remove_sys_dev_entry(dev
);
1190 device_remove_file(dev
, &dev_attr_dev
);
1193 device_remove_class_symlinks(dev
);
1195 mutex_lock(&dev
->class->p
->mutex
);
1196 /* notify any interfaces that the device is now gone */
1197 list_for_each_entry(class_intf
,
1198 &dev
->class->p
->interfaces
, node
)
1199 if (class_intf
->remove_dev
)
1200 class_intf
->remove_dev(dev
, class_intf
);
1201 /* remove the device from the class list */
1202 klist_del(&dev
->knode_class
);
1203 mutex_unlock(&dev
->class->p
->mutex
);
1205 device_remove_file(dev
, &dev_attr_uevent
);
1206 device_remove_attrs(dev
);
1207 bus_remove_device(dev
);
1208 device_pm_remove(dev
);
1209 driver_deferred_probe_del(dev
);
1211 /* Notify the platform of the removal, in case they
1212 * need to do anything...
1214 if (platform_notify_remove
)
1215 platform_notify_remove(dev
);
1217 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
1218 BUS_NOTIFY_REMOVED_DEVICE
, dev
);
1219 kobject_uevent(&dev
->kobj
, KOBJ_REMOVE
);
1220 cleanup_device_parent(dev
);
1221 kobject_del(&dev
->kobj
);
1224 EXPORT_SYMBOL_GPL(device_del
);
1227 * device_unregister - unregister device from system.
1228 * @dev: device going away.
1230 * We do this in two parts, like we do device_register(). First,
1231 * we remove it from all the subsystems with device_del(), then
1232 * we decrement the reference count via put_device(). If that
1233 * is the final reference count, the device will be cleaned up
1234 * via device_release() above. Otherwise, the structure will
1235 * stick around until the final reference to the device is dropped.
1237 void device_unregister(struct device
*dev
)
1239 pr_debug("device: '%s': %s\n", dev_name(dev
), __func__
);
1243 EXPORT_SYMBOL_GPL(device_unregister
);
1245 static struct device
*next_device(struct klist_iter
*i
)
1247 struct klist_node
*n
= klist_next(i
);
1248 struct device
*dev
= NULL
;
1249 struct device_private
*p
;
1252 p
= to_device_private_parent(n
);
1259 * device_get_devnode - path of device node file
1261 * @mode: returned file access mode
1262 * @uid: returned file owner
1263 * @gid: returned file group
1264 * @tmp: possibly allocated string
1266 * Return the relative path of a possible device node.
1267 * Non-default names may need to allocate a memory to compose
1268 * a name. This memory is returned in tmp and needs to be
1269 * freed by the caller.
1271 const char *device_get_devnode(struct device
*dev
,
1272 umode_t
*mode
, kuid_t
*uid
, kgid_t
*gid
,
1279 /* the device type may provide a specific name */
1280 if (dev
->type
&& dev
->type
->devnode
)
1281 *tmp
= dev
->type
->devnode(dev
, mode
, uid
, gid
);
1285 /* the class may provide a specific name */
1286 if (dev
->class && dev
->class->devnode
)
1287 *tmp
= dev
->class->devnode(dev
, mode
);
1291 /* return name without allocation, tmp == NULL */
1292 if (strchr(dev_name(dev
), '!') == NULL
)
1293 return dev_name(dev
);
1295 /* replace '!' in the name with '/' */
1296 *tmp
= kstrdup(dev_name(dev
), GFP_KERNEL
);
1299 while ((s
= strchr(*tmp
, '!')))
1305 * device_for_each_child - device child iterator.
1306 * @parent: parent struct device.
1307 * @fn: function to be called for each device.
1308 * @data: data for the callback.
1310 * Iterate over @parent's child devices, and call @fn for each,
1313 * We check the return of @fn each time. If it returns anything
1314 * other than 0, we break out and return that value.
1316 int device_for_each_child(struct device
*parent
, void *data
,
1317 int (*fn
)(struct device
*dev
, void *data
))
1319 struct klist_iter i
;
1320 struct device
*child
;
1326 klist_iter_init(&parent
->p
->klist_children
, &i
);
1327 while ((child
= next_device(&i
)) && !error
)
1328 error
= fn(child
, data
);
1329 klist_iter_exit(&i
);
1332 EXPORT_SYMBOL_GPL(device_for_each_child
);
1335 * device_find_child - device iterator for locating a particular device.
1336 * @parent: parent struct device
1337 * @match: Callback function to check device
1338 * @data: Data to pass to match function
1340 * This is similar to the device_for_each_child() function above, but it
1341 * returns a reference to a device that is 'found' for later use, as
1342 * determined by the @match callback.
1344 * The callback should return 0 if the device doesn't match and non-zero
1345 * if it does. If the callback returns non-zero and a reference to the
1346 * current device can be obtained, this function will return to the caller
1347 * and not iterate over any more devices.
1349 * NOTE: you will need to drop the reference with put_device() after use.
1351 struct device
*device_find_child(struct device
*parent
, void *data
,
1352 int (*match
)(struct device
*dev
, void *data
))
1354 struct klist_iter i
;
1355 struct device
*child
;
1360 klist_iter_init(&parent
->p
->klist_children
, &i
);
1361 while ((child
= next_device(&i
)))
1362 if (match(child
, data
) && get_device(child
))
1364 klist_iter_exit(&i
);
1367 EXPORT_SYMBOL_GPL(device_find_child
);
1369 int __init
devices_init(void)
1371 devices_kset
= kset_create_and_add("devices", &device_uevent_ops
, NULL
);
1374 dev_kobj
= kobject_create_and_add("dev", NULL
);
1377 sysfs_dev_block_kobj
= kobject_create_and_add("block", dev_kobj
);
1378 if (!sysfs_dev_block_kobj
)
1379 goto block_kobj_err
;
1380 sysfs_dev_char_kobj
= kobject_create_and_add("char", dev_kobj
);
1381 if (!sysfs_dev_char_kobj
)
1387 kobject_put(sysfs_dev_block_kobj
);
1389 kobject_put(dev_kobj
);
1391 kset_unregister(devices_kset
);
1395 static int device_check_offline(struct device
*dev
, void *not_used
)
1399 ret
= device_for_each_child(dev
, NULL
, device_check_offline
);
1403 return device_supports_offline(dev
) && !dev
->offline
? -EBUSY
: 0;
1407 * device_offline - Prepare the device for hot-removal.
1408 * @dev: Device to be put offline.
1410 * Execute the device bus type's .offline() callback, if present, to prepare
1411 * the device for a subsequent hot-removal. If that succeeds, the device must
1412 * not be used until either it is removed or its bus type's .online() callback
1415 * Call under device_hotplug_lock.
1417 int device_offline(struct device
*dev
)
1421 if (dev
->offline_disabled
)
1424 ret
= device_for_each_child(dev
, NULL
, device_check_offline
);
1429 if (device_supports_offline(dev
)) {
1433 ret
= dev
->bus
->offline(dev
);
1435 kobject_uevent(&dev
->kobj
, KOBJ_OFFLINE
);
1436 dev
->offline
= true;
1446 * device_online - Put the device back online after successful device_offline().
1447 * @dev: Device to be put back online.
1449 * If device_offline() has been successfully executed for @dev, but the device
1450 * has not been removed subsequently, execute its bus type's .online() callback
1451 * to indicate that the device can be used again.
1453 * Call under device_hotplug_lock.
1455 int device_online(struct device
*dev
)
1460 if (device_supports_offline(dev
)) {
1462 ret
= dev
->bus
->online(dev
);
1464 kobject_uevent(&dev
->kobj
, KOBJ_ONLINE
);
1465 dev
->offline
= false;
1476 struct root_device
{
1478 struct module
*owner
;
1481 static inline struct root_device
*to_root_device(struct device
*d
)
1483 return container_of(d
, struct root_device
, dev
);
1486 static void root_device_release(struct device
*dev
)
1488 kfree(to_root_device(dev
));
1492 * __root_device_register - allocate and register a root device
1493 * @name: root device name
1494 * @owner: owner module of the root device, usually THIS_MODULE
1496 * This function allocates a root device and registers it
1497 * using device_register(). In order to free the returned
1498 * device, use root_device_unregister().
1500 * Root devices are dummy devices which allow other devices
1501 * to be grouped under /sys/devices. Use this function to
1502 * allocate a root device and then use it as the parent of
1503 * any device which should appear under /sys/devices/{name}
1505 * The /sys/devices/{name} directory will also contain a
1506 * 'module' symlink which points to the @owner directory
1509 * Returns &struct device pointer on success, or ERR_PTR() on error.
1511 * Note: You probably want to use root_device_register().
1513 struct device
*__root_device_register(const char *name
, struct module
*owner
)
1515 struct root_device
*root
;
1518 root
= kzalloc(sizeof(struct root_device
), GFP_KERNEL
);
1520 return ERR_PTR(err
);
1522 err
= dev_set_name(&root
->dev
, "%s", name
);
1525 return ERR_PTR(err
);
1528 root
->dev
.release
= root_device_release
;
1530 err
= device_register(&root
->dev
);
1532 put_device(&root
->dev
);
1533 return ERR_PTR(err
);
1536 #ifdef CONFIG_MODULES /* gotta find a "cleaner" way to do this */
1538 struct module_kobject
*mk
= &owner
->mkobj
;
1540 err
= sysfs_create_link(&root
->dev
.kobj
, &mk
->kobj
, "module");
1542 device_unregister(&root
->dev
);
1543 return ERR_PTR(err
);
1545 root
->owner
= owner
;
1551 EXPORT_SYMBOL_GPL(__root_device_register
);
1554 * root_device_unregister - unregister and free a root device
1555 * @dev: device going away
1557 * This function unregisters and cleans up a device that was created by
1558 * root_device_register().
1560 void root_device_unregister(struct device
*dev
)
1562 struct root_device
*root
= to_root_device(dev
);
1565 sysfs_remove_link(&root
->dev
.kobj
, "module");
1567 device_unregister(dev
);
1569 EXPORT_SYMBOL_GPL(root_device_unregister
);
1572 static void device_create_release(struct device
*dev
)
1574 pr_debug("device: '%s': %s\n", dev_name(dev
), __func__
);
1578 static struct device
*
1579 device_create_groups_vargs(struct class *class, struct device
*parent
,
1580 dev_t devt
, void *drvdata
,
1581 const struct attribute_group
**groups
,
1582 const char *fmt
, va_list args
)
1584 struct device
*dev
= NULL
;
1585 int retval
= -ENODEV
;
1587 if (class == NULL
|| IS_ERR(class))
1590 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
1596 device_initialize(dev
);
1599 dev
->parent
= parent
;
1600 dev
->groups
= groups
;
1601 dev
->release
= device_create_release
;
1602 dev_set_drvdata(dev
, drvdata
);
1604 retval
= kobject_set_name_vargs(&dev
->kobj
, fmt
, args
);
1608 retval
= device_add(dev
);
1616 return ERR_PTR(retval
);
1620 * device_create_vargs - creates a device and registers it with sysfs
1621 * @class: pointer to the struct class that this device should be registered to
1622 * @parent: pointer to the parent struct device of this new device, if any
1623 * @devt: the dev_t for the char device to be added
1624 * @drvdata: the data to be added to the device for callbacks
1625 * @fmt: string for the device's name
1626 * @args: va_list for the device's name
1628 * This function can be used by char device classes. A struct device
1629 * will be created in sysfs, registered to the specified class.
1631 * A "dev" file will be created, showing the dev_t for the device, if
1632 * the dev_t is not 0,0.
1633 * If a pointer to a parent struct device is passed in, the newly created
1634 * struct device will be a child of that device in sysfs.
1635 * The pointer to the struct device will be returned from the call.
1636 * Any further sysfs files that might be required can be created using this
1639 * Returns &struct device pointer on success, or ERR_PTR() on error.
1641 * Note: the struct class passed to this function must have previously
1642 * been created with a call to class_create().
1644 struct device
*device_create_vargs(struct class *class, struct device
*parent
,
1645 dev_t devt
, void *drvdata
, const char *fmt
,
1648 return device_create_groups_vargs(class, parent
, devt
, drvdata
, NULL
,
1651 EXPORT_SYMBOL_GPL(device_create_vargs
);
1654 * device_create - creates a device and registers it with sysfs
1655 * @class: pointer to the struct class that this device should be registered to
1656 * @parent: pointer to the parent struct device of this new device, if any
1657 * @devt: the dev_t for the char device to be added
1658 * @drvdata: the data to be added to the device for callbacks
1659 * @fmt: string for the device's name
1661 * This function can be used by char device classes. A struct device
1662 * will be created in sysfs, registered to the specified class.
1664 * A "dev" file will be created, showing the dev_t for the device, if
1665 * the dev_t is not 0,0.
1666 * If a pointer to a parent struct device is passed in, the newly created
1667 * struct device will be a child of that device in sysfs.
1668 * The pointer to the struct device will be returned from the call.
1669 * Any further sysfs files that might be required can be created using this
1672 * Returns &struct device pointer on success, or ERR_PTR() on error.
1674 * Note: the struct class passed to this function must have previously
1675 * been created with a call to class_create().
1677 struct device
*device_create(struct class *class, struct device
*parent
,
1678 dev_t devt
, void *drvdata
, const char *fmt
, ...)
1683 va_start(vargs
, fmt
);
1684 dev
= device_create_vargs(class, parent
, devt
, drvdata
, fmt
, vargs
);
1688 EXPORT_SYMBOL_GPL(device_create
);
1691 * device_create_with_groups - creates a device and registers it with sysfs
1692 * @class: pointer to the struct class that this device should be registered to
1693 * @parent: pointer to the parent struct device of this new device, if any
1694 * @devt: the dev_t for the char device to be added
1695 * @drvdata: the data to be added to the device for callbacks
1696 * @groups: NULL-terminated list of attribute groups to be created
1697 * @fmt: string for the device's name
1699 * This function can be used by char device classes. A struct device
1700 * will be created in sysfs, registered to the specified class.
1701 * Additional attributes specified in the groups parameter will also
1702 * be created automatically.
1704 * A "dev" file will be created, showing the dev_t for the device, if
1705 * the dev_t is not 0,0.
1706 * If a pointer to a parent struct device is passed in, the newly created
1707 * struct device will be a child of that device in sysfs.
1708 * The pointer to the struct device will be returned from the call.
1709 * Any further sysfs files that might be required can be created using this
1712 * Returns &struct device pointer on success, or ERR_PTR() on error.
1714 * Note: the struct class passed to this function must have previously
1715 * been created with a call to class_create().
1717 struct device
*device_create_with_groups(struct class *class,
1718 struct device
*parent
, dev_t devt
,
1720 const struct attribute_group
**groups
,
1721 const char *fmt
, ...)
1726 va_start(vargs
, fmt
);
1727 dev
= device_create_groups_vargs(class, parent
, devt
, drvdata
, groups
,
1732 EXPORT_SYMBOL_GPL(device_create_with_groups
);
1734 static int __match_devt(struct device
*dev
, const void *data
)
1736 const dev_t
*devt
= data
;
1738 return dev
->devt
== *devt
;
1742 * device_destroy - removes a device that was created with device_create()
1743 * @class: pointer to the struct class that this device was registered with
1744 * @devt: the dev_t of the device that was previously registered
1746 * This call unregisters and cleans up a device that was created with a
1747 * call to device_create().
1749 void device_destroy(struct class *class, dev_t devt
)
1753 dev
= class_find_device(class, NULL
, &devt
, __match_devt
);
1756 device_unregister(dev
);
1759 EXPORT_SYMBOL_GPL(device_destroy
);
1762 * device_rename - renames a device
1763 * @dev: the pointer to the struct device to be renamed
1764 * @new_name: the new name of the device
1766 * It is the responsibility of the caller to provide mutual
1767 * exclusion between two different calls of device_rename
1768 * on the same device to ensure that new_name is valid and
1769 * won't conflict with other devices.
1771 * Note: Don't call this function. Currently, the networking layer calls this
1772 * function, but that will change. The following text from Kay Sievers offers
1775 * Renaming devices is racy at many levels, symlinks and other stuff are not
1776 * replaced atomically, and you get a "move" uevent, but it's not easy to
1777 * connect the event to the old and new device. Device nodes are not renamed at
1778 * all, there isn't even support for that in the kernel now.
1780 * In the meantime, during renaming, your target name might be taken by another
1781 * driver, creating conflicts. Or the old name is taken directly after you
1782 * renamed it -- then you get events for the same DEVPATH, before you even see
1783 * the "move" event. It's just a mess, and nothing new should ever rely on
1784 * kernel device renaming. Besides that, it's not even implemented now for
1785 * other things than (driver-core wise very simple) network devices.
1787 * We are currently about to change network renaming in udev to completely
1788 * disallow renaming of devices in the same namespace as the kernel uses,
1789 * because we can't solve the problems properly, that arise with swapping names
1790 * of multiple interfaces without races. Means, renaming of eth[0-9]* will only
1791 * be allowed to some other name than eth[0-9]*, for the aforementioned
1794 * Make up a "real" name in the driver before you register anything, or add
1795 * some other attributes for userspace to find the device, or use udev to add
1796 * symlinks -- but never rename kernel devices later, it's a complete mess. We
1797 * don't even want to get into that and try to implement the missing pieces in
1798 * the core. We really have other pieces to fix in the driver core mess. :)
1800 int device_rename(struct device
*dev
, const char *new_name
)
1802 struct kobject
*kobj
= &dev
->kobj
;
1803 char *old_device_name
= NULL
;
1806 dev
= get_device(dev
);
1810 dev_dbg(dev
, "renaming to %s\n", new_name
);
1812 old_device_name
= kstrdup(dev_name(dev
), GFP_KERNEL
);
1813 if (!old_device_name
) {
1819 error
= sysfs_rename_link_ns(&dev
->class->p
->subsys
.kobj
,
1820 kobj
, old_device_name
,
1821 new_name
, kobject_namespace(kobj
));
1826 error
= kobject_rename(kobj
, new_name
);
1833 kfree(old_device_name
);
1837 EXPORT_SYMBOL_GPL(device_rename
);
1839 static int device_move_class_links(struct device
*dev
,
1840 struct device
*old_parent
,
1841 struct device
*new_parent
)
1846 sysfs_remove_link(&dev
->kobj
, "device");
1848 error
= sysfs_create_link(&dev
->kobj
, &new_parent
->kobj
,
1854 * device_move - moves a device to a new parent
1855 * @dev: the pointer to the struct device to be moved
1856 * @new_parent: the new parent of the device (can by NULL)
1857 * @dpm_order: how to reorder the dpm_list
1859 int device_move(struct device
*dev
, struct device
*new_parent
,
1860 enum dpm_order dpm_order
)
1863 struct device
*old_parent
;
1864 struct kobject
*new_parent_kobj
;
1866 dev
= get_device(dev
);
1871 new_parent
= get_device(new_parent
);
1872 new_parent_kobj
= get_device_parent(dev
, new_parent
);
1874 pr_debug("device: '%s': %s: moving to '%s'\n", dev_name(dev
),
1875 __func__
, new_parent
? dev_name(new_parent
) : "<NULL>");
1876 error
= kobject_move(&dev
->kobj
, new_parent_kobj
);
1878 cleanup_glue_dir(dev
, new_parent_kobj
);
1879 put_device(new_parent
);
1882 old_parent
= dev
->parent
;
1883 dev
->parent
= new_parent
;
1885 klist_remove(&dev
->p
->knode_parent
);
1887 klist_add_tail(&dev
->p
->knode_parent
,
1888 &new_parent
->p
->klist_children
);
1889 set_dev_node(dev
, dev_to_node(new_parent
));
1893 error
= device_move_class_links(dev
, old_parent
, new_parent
);
1895 /* We ignore errors on cleanup since we're hosed anyway... */
1896 device_move_class_links(dev
, new_parent
, old_parent
);
1897 if (!kobject_move(&dev
->kobj
, &old_parent
->kobj
)) {
1899 klist_remove(&dev
->p
->knode_parent
);
1900 dev
->parent
= old_parent
;
1902 klist_add_tail(&dev
->p
->knode_parent
,
1903 &old_parent
->p
->klist_children
);
1904 set_dev_node(dev
, dev_to_node(old_parent
));
1907 cleanup_glue_dir(dev
, new_parent_kobj
);
1908 put_device(new_parent
);
1912 switch (dpm_order
) {
1913 case DPM_ORDER_NONE
:
1915 case DPM_ORDER_DEV_AFTER_PARENT
:
1916 device_pm_move_after(dev
, new_parent
);
1918 case DPM_ORDER_PARENT_BEFORE_DEV
:
1919 device_pm_move_before(new_parent
, dev
);
1921 case DPM_ORDER_DEV_LAST
:
1922 device_pm_move_last(dev
);
1926 put_device(old_parent
);
1932 EXPORT_SYMBOL_GPL(device_move
);
1935 * device_shutdown - call ->shutdown() on each device to shutdown.
1937 void device_shutdown(void)
1939 struct device
*dev
, *parent
;
1941 spin_lock(&devices_kset
->list_lock
);
1943 * Walk the devices list backward, shutting down each in turn.
1944 * Beware that device unplug events may also start pulling
1945 * devices offline, even as the system is shutting down.
1947 while (!list_empty(&devices_kset
->list
)) {
1948 dev
= list_entry(devices_kset
->list
.prev
, struct device
,
1952 * hold reference count of device's parent to
1953 * prevent it from being freed because parent's
1954 * lock is to be held
1956 parent
= get_device(dev
->parent
);
1959 * Make sure the device is off the kset list, in the
1960 * event that dev->*->shutdown() doesn't remove it.
1962 list_del_init(&dev
->kobj
.entry
);
1963 spin_unlock(&devices_kset
->list_lock
);
1965 /* hold lock to avoid race with probe/release */
1967 device_lock(parent
);
1970 /* Don't allow any more runtime suspends */
1971 pm_runtime_get_noresume(dev
);
1972 pm_runtime_barrier(dev
);
1974 if (dev
->bus
&& dev
->bus
->shutdown
) {
1976 dev_info(dev
, "shutdown\n");
1977 dev
->bus
->shutdown(dev
);
1978 } else if (dev
->driver
&& dev
->driver
->shutdown
) {
1980 dev_info(dev
, "shutdown\n");
1981 dev
->driver
->shutdown(dev
);
1986 device_unlock(parent
);
1991 spin_lock(&devices_kset
->list_lock
);
1993 spin_unlock(&devices_kset
->list_lock
);
1997 * Device logging functions
2000 #ifdef CONFIG_PRINTK
2002 create_syslog_header(const struct device
*dev
, char *hdr
, size_t hdrlen
)
2008 subsys
= dev
->class->name
;
2010 subsys
= dev
->bus
->name
;
2014 pos
+= snprintf(hdr
+ pos
, hdrlen
- pos
, "SUBSYSTEM=%s", subsys
);
2019 * Add device identifier DEVICE=:
2023 * +sound:card0 subsystem:devname
2025 if (MAJOR(dev
->devt
)) {
2028 if (strcmp(subsys
, "block") == 0)
2033 pos
+= snprintf(hdr
+ pos
, hdrlen
- pos
,
2035 c
, MAJOR(dev
->devt
), MINOR(dev
->devt
));
2036 } else if (strcmp(subsys
, "net") == 0) {
2037 struct net_device
*net
= to_net_dev(dev
);
2040 pos
+= snprintf(hdr
+ pos
, hdrlen
- pos
,
2041 "DEVICE=n%u", net
->ifindex
);
2044 pos
+= snprintf(hdr
+ pos
, hdrlen
- pos
,
2045 "DEVICE=+%s:%s", subsys
, dev_name(dev
));
2054 dev_WARN(dev
, "device/subsystem name too long");
2058 int dev_vprintk_emit(int level
, const struct device
*dev
,
2059 const char *fmt
, va_list args
)
2064 hdrlen
= create_syslog_header(dev
, hdr
, sizeof(hdr
));
2066 return vprintk_emit(0, level
, hdrlen
? hdr
: NULL
, hdrlen
, fmt
, args
);
2068 EXPORT_SYMBOL(dev_vprintk_emit
);
2070 int dev_printk_emit(int level
, const struct device
*dev
, const char *fmt
, ...)
2075 va_start(args
, fmt
);
2077 r
= dev_vprintk_emit(level
, dev
, fmt
, args
);
2083 EXPORT_SYMBOL(dev_printk_emit
);
2085 static int __dev_printk(const char *level
, const struct device
*dev
,
2086 struct va_format
*vaf
)
2089 return printk("%s(NULL device *): %pV", level
, vaf
);
2091 return dev_printk_emit(level
[1] - '0', dev
,
2093 dev_driver_string(dev
), dev_name(dev
), vaf
);
2096 int dev_printk(const char *level
, const struct device
*dev
,
2097 const char *fmt
, ...)
2099 struct va_format vaf
;
2103 va_start(args
, fmt
);
2108 r
= __dev_printk(level
, dev
, &vaf
);
2114 EXPORT_SYMBOL(dev_printk
);
2116 #define define_dev_printk_level(func, kern_level) \
2117 int func(const struct device *dev, const char *fmt, ...) \
2119 struct va_format vaf; \
2123 va_start(args, fmt); \
2128 r = __dev_printk(kern_level, dev, &vaf); \
2134 EXPORT_SYMBOL(func);
2136 define_dev_printk_level(dev_emerg
, KERN_EMERG
);
2137 define_dev_printk_level(dev_alert
, KERN_ALERT
);
2138 define_dev_printk_level(dev_crit
, KERN_CRIT
);
2139 define_dev_printk_level(dev_err
, KERN_ERR
);
2140 define_dev_printk_level(dev_warn
, KERN_WARNING
);
2141 define_dev_printk_level(dev_notice
, KERN_NOTICE
);
2142 define_dev_printk_level(_dev_info
, KERN_INFO
);